1. Field of the Invention
The present invention relates to a substrate processing apparatus for processing substrates, such as semiconductor wafers or glass substrates for LCDs by a cleaning process or the like.
2. Description of the Related Art
A semiconductor device manufacturing process uses a substrate cleaning system for cleaning semiconductor wafers (hereinafter referred to simply as “wafers”) with a cleaning liquid, such as a chemical solution or pure water, to remove contaminants, such as particles, organic contaminants and metallic impurities, from the wafers. There are various known batch substrate cleaning apparatus and known single-wafer substrate cleaning apparatus for such a substrate cleaning system. A prior art substrate-cleaning apparatus disclosed in Japanese patent laid-open publication “JP Hei08-78368 A” has a plate disposed close to the surface of a wafer, and supplies a processing liquid or a processing gas into the gap between the surface of the wafer and the plate for a cleaning process. This prior art substrate-cleaning apparatus has an advantage in that the same is capable of achieving a cleaning process at a low consumption of the processing liquid or the processing gas.
In this prior art substrate cleaning apparatus, however, a processing medium supply means for supplying the processing liquid or the processing gas to the substrate is disposed in a substrate-processing space and is exposed to a substrate-processing atmosphere. Therefore, it is possible that the substrate-processing atmosphere produced by the processing medium supply means for supplying the processing liquid or the processing gas diffuses and exerts bad influence on the processed substrate. It is also possible that the processing medium supply means is contaminated with an atmosphere of the processing liquid or the processing gas diffused during a substrate-processing process, in which the processing medium supply means is held in a waiting state. If the substrate cleaning apparatus is provided with a plurality of processing medium supply means, it is possible that the plurality processing medium supply means exert bad influences on each other.
In addition, it is also possible that the processing atmosphere of the processing liquid remains in a cleaning unit after the completion of the cleaning process, and the processing liquid remaining in the processing unit exerts bad influences on the processed wafer. A high-temperature processing liquid is liable to remain in mist in an upper part of the cleaning unit and hence it is highly possible for the mist of the processing liquid to exert bad influences on the wafer.
A substrate-processing atmosphere of the processing liquid is liable to leak from the conventional substrate processing device when a substrate is loaded into or unloaded from the substrate processing device, and there is the possibility that a carrying device and such included in the cleaning system are corroded by the leaked substrate-processing atmosphere of the processing liquid. Therefore the carrying device and such must be rust-proofed. However, most carrying devices and such are formed from explosion-proof materials. Therefore, materials for forming the components of the carrying devices and the like need to be both rustproof and explosion-proof and it is difficult to select such materials.